@ GreggBz:
Blame ACPI, not the OS. It's a horrible, bloated specification.
How about if I blame both? :-)
ACPI might be the root cause, but Windows is the visible factor, and since M$ has spend much of their power controlling the standards, why not control this one too.
In any case, it's the entire system we judge, hardware, ACPI, OS and all, and, quite frankly, they suck.
Ed.